The invention relates to a two-roll machine for high-pressure crushing of granular material, in particular a roll press for interparticle comminution or compacting/briquetting, with two counter-rotating driven rolls mounted rotatably in bearing housings and separated from one another by a roll gap. Mounted on the roll shaft drive journal of each of the rolls extending out of the machine frame as a shaft-mounted gearbox is a planetary gear unit whose input stage is driven by a drive motor.
On roll mills for so-called interparticle comminution, the individual pieces or particles of the material to be ground drawn into the roll gap by friction, e.g. cement raw material, cement clinker, ores or similar materials, are pressed together and mutually comminuted in a material bed, in other words in a material pile pressed together between the two roll surfaces under high pressure, whereby one also speaks of a roll press instead of a roll mill. On such known roll presses, cf. e.g. brochure “Rollenpressen” (Roll Presses) No. 2-300d of KHD Humboldt Wedag AG dated September 1994, one of the two rolls is designed as a fixed roll that is supported by means of its bearing housing against end walls of the machine frame, while the other roll designed as a floating roll is supported via its bearing housing on hydraulic cylinders with which the roll pressure force is applied.
For the drive of such roll presses it is common to allow two roll shaft drive journals to extend out of the machine frame, on each of which a planetary gear unit (epicyclic gear unit) is shaft-mounted, and whose input stage is driven by an electric motor, and in the case of large roll presses via a universal-joint shaft and a coupling. It is common here to make the connection between the hollow shaft on the output side of the gear unit and the drive journal of the roll press rolls by means of a so-called shrink disc connection that has an externally clamping, hydraulically actuated clamping set with clamping rings that is suitable as a backlash-free non-positive connection for the transmission of even very high torques.
The load of the heavy shaft-mounted gearbox is not supported on the ground; the gearboxes are over-mounted on the drive journal. Until now, rope cranes have been generally used for installation and removal of the shaft-mounted gearboxes. During installation and removal, the drive journal and the attached shaft-mounted gearbox must be aligned on one axis and exactly positioned horizontally and vertically. Such levelling is difficult to achieve, particularly as the lifting point of the gear unit is not at its center of gravity, so that the danger cannot be ruled out that if the shaft-mounted gearbox is not exactly positioned, damage can be caused to the surface of the drive journals and to the gearbox hollow shafts during installation and removal with pushing on and pulling off of the gear unit and hydraulic actuation of the shrink disc connection. The installation and removal of the shaft-mounted gearboxes on roll presses is not a one-off operation, because for reasons of repair (e.g. with worn rolls), the operators of such roll presses need to be able to remove and reinstall these rolls in the simplest and fastest possible manner, with the shaft-mounted gearboxes having to be removed from their drive journals.